French justice authorities scrambled for clues Thursday into the assassination of three women in a Kurdish institute in Paris — a crime that appeared to have clear political overtones. Two of the victims were shot in the head, in what Interior Minister Manuel Valls said was “no doubt an execution.” One of them was Sakine Cansiz, a co-founder of the Kurdistan Workers’ Party (PKK), a group that has waged an often violent Kurdish separatist struggle against Turkey and which has been designated a terrorist organization by the U.S. and the E.U.

The slayings come at a sensitive time. Turkish media report that the Ankara government has recently made progress toward ending the nearly three decades of violence through unpublicized peace talks with some PKK leaders, included jailed PKK chief Abdullah Ocalan. Such peace talks are not supported by all PKK militants — a strategic division that may have caused a schism within the group.

Reports on Thursday quoted top Turkish politicians speculating that the Paris murders were a result of “an internal feud” within the PKK. But that claim was rejected by many of the hundreds of Kurds who gathered Thursday morning outside the Kurdish Information Center in Paris where the killings took place; instead, they blamed Ankara.

“The murder of these three Kurdish women, at this time, is a political crime,” Berivan Akyol, a worker at the center, told French news channel i-télé. “These three victims … represent all Kurds.”

The deceased had apparently been shot Wednesday afternoon and were discovered around 1 a.m. Thursday after concerned colleagues failed to reach them by phone. In addition to PKK co-founder Cansiz, a woman described as a representative of the Brussels-based Kurdistan National Congress was among the dead. According to the Firat news agency — which is considered sympathetic to the Kurdish cause — two of the women were shot in the head and a third in the stomach by a silencer-fitted gun.

French security officials tell TIME it’s too early to openly speculate about who was behind the killings, though two obvious theories are already under consideration. Given the brutality with which Turkey has at times sought to suppress Kurdish nationalism and the violent methods sometimes used by the PKK in its struggle for autonomy, French authorities believe that both scenarios — an assassination ordered by the PKK’s enemies or a deadly factional split — are equally plausible.

The first thesis, said a French security official who did not want to be quoted, might aim at weakening PKK factions hostile to negotiating an end to the conflict. The second, he added, might seek to further widen the split between rival PKK camps over peace talks, thereby hampering further efforts in striking a deal with Turkey. But whatever the motive for the killings, Valls pledged to bring to justice those responsible.

“The antiterrorism and [homicide] units have been mobilized to shed light on this absolutely intolerable act,” Valls said Thursday morning outside the Kurdish center, not far from Paris’ Gare du Nord train station. “I have come to express my compassion for those who are close to these three women.”

Valls was also addressing the hundreds of sorrowful and angry Kurds who’d flocked to the center early Thursday, chanting Ocalan’s name and “We are all PKK.” About 150,000 Kurds live in France, many as political exiles. Meanwhile, despite the PKK’s terrorist designation, the organization has enjoyed the ambivalent support of many in Europe sympathetic to the Kurdish plight.

That ambivalence has at times also been reflected by French justice officials. While authorities have repeatedly arrested militants suspected of organizing or financing acts of PKK terrorism, less troublesome party members and sympathizers are generally left alone. The 28-year battle between the PKK and Turkey has claimed about 40,000 lives, with violence at times having spilled into other countries. The chants of “A political solution for Kurdistan” among Kurdish mourners in Paris on Thursday appeared to express hopes that this new trio of deaths in that struggle will be the last.